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IMAAVY is an immunoselective FcRn blocker designed to target and reduce pathogenic immunoglobulin G (IgG) autoantibodies while also preserving B-cell function
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Warm autoimmune hemolytic anemia is a rare, life-threatening disease in which autoantibodies cause the destruction of red blood cells, leading to severe anemia and debilitating fatigue
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The approval is based on the pivotal Phase 2/3 study which demonstrated durable hemoglobin responsea
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A mean increase in hemoglobin of 1 g/dL at Week 1b and improvement in FACIT-Fatiguec score at Week 24 were observed in IMAAVY-treated patientsd
SPRING HOUSE, Pa. (August 24, 2026) - Johnson & Johnson (NYSE: JNJ) today announced the U.S. Food and Drug Administration (FDA) approval of IMAAVY® (nipocalimab-aahu) for the treatment of warm autoimmune hemolytic anemia (wAIHA) – a rare, life-threatening autoantibody disease – in adults and pediatric patients 12 years of age and older currently or previously treated with corticosteroids. The approval, which follows FDA Priority Review, marks the first time a therapy was proven safe and effective specifically for the treatment of wAIHA.1
“Living with wAIHA often means relentless fatigue and the constant uncertainty of not knowing what tomorrow will bring,” said Karen Jones, President and Executive Director, wAIHA Warriors.e “Patients may cycle through periods where they start to feel like themselves again — and then their hemoglobin drops, the exhaustion returns, and they’re back to square one. For the first time, our community has a treatment specifically for our disease.”
Addressing serious unmet need in wAIHA
In wAIHA, pathogenic immunoglobulin G (IgG) autoantibodies attach to and destroy red blood cells, causing severe anemia, profound fatigue, and a significantly increased risk of morbidity and mortality.2 Previously, available treatment options only included corticosteroids and immunosuppressants — therapies that suppress the entire immune system without specifically targeting the IgG autoantibodies driving the disease.3
“The Phase 2/3 ENERGY study demonstrates that targeting pathogenic IgG can meaningfully change the treatment paradigm for wAIHA,” said David Kuter, M.D., D.Phil., Distinguished Physician, Massachusetts General Hospital and Professor of Medicine at Harvard Medical School.f “More patients treated with IMAAVY achieved a durable hemoglobin response compared with placebo — meaning their red blood cell levels went up and stayed up. For patients, this approval means that they now have a therapy with a proven safety profile that targets the disease-driving autoantibodies in wAIHA.”
Clinical evidence summary of IMAAVY in wAIHA
The primary endpoint of the Phase 2/3 ENERGY study was durable hemoglobin (Hgb) response,a a stringent endpoint definition that reflects meaningful increases in Hgb levels over time.4,5 The randomized, placebo-controlled trial demonstrated approximately three times as many patients receiving the approved dose of IMAAVYg achieved durable Hgb levels versus placebo by 24 weeks.5,h Overall patients in this treatment group showed a mean increase in Hgb of 1g/dL at Week 1.5,b In addition, IMAAVY was associated with a 3.5-point higher mean FACIT-Fatiguec score versus placebo at Week 24, with higher scores defined as less fatigue.5,d In the ENERGY study IMAAVY demonstrated a safety profile consistent with the established safety profile of IMAAVY in generalized myasthenia gravis (gMG).4 The most common adverse reactions (≥10%) in patients with wAIHA treated with IMAAVY were peripheral edema, diarrhea, and fever.5
The full results of the ENERGY study were presented at the European Hematology Association 2026 meeting in June 2026.
Building on a proven approach to autoantibody-driven disease
“Today’s announcement marks the second approval for IMAAVY and is an extraordinary milestone for people living with warm autoimmune hemolytic anemia, an underserved community that has waited far too long for an FDA-approved treatment,” said David M. Lee, M.D., Ph.D., Global Immunology Therapeutic Area Head, Johnson & Johnson. “As the first therapy approved for wAIHA, IMAAVY has the potential to redefine the management of wAIHA, particularly for those with uncontrolled disease. This milestone reinforces our motivation to continue pursuing advanced therapies for people living with allo- and autoantibody diseases like wAIHA.”
IMAAVY was approved in the United States in April 2025 for the treatment of gMG in adult and pediatric patients 12 years of age and older who are acetylcholine receptor (AChR) or muscle-specific kinase (MuSK) antibody positive.5
Johnson & Johnson is committed to helping patients access our treatments. Once a decision has been made to prescribe IMAAVY, the IMAAVY withMe patient support program provides personalized support including educational resources, a dedicated Nurse Navigator,i and cost support options – regardless of insurance type.
Editor’s Notes:
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Durable hemoglobin (Hgb) response, the primary endpoint of the Phase 2/3 ENERGY trial, is defined as Hgb concentration ≥10 g/dL and an increase from baseline in Hgb ≥2 g/dL for at least 28 days (where criteria was met starting by Week 16 of the double-blind period), without the need of rescue therapy5
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A mean increase of 1 g/dL in Hgb was observed at Week 1. Among the responders, the median time to first Hgb response was 4.1 (range: 1 to 12) weeks in patients treated with IMAAVY 30 mg/kg every 4 weeks, compared to 12.1 (range: 4 to 16) weeks in the placebo group. Results are considered descriptive based on the study’s pre-specified statistical analysis plan[6]
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Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue)
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Mean change from baseline of FACIT-Fatigue score at Week 24, a key secondary endpoint, with mean difference of 3.51 (95% CI: 0.64; 6.39) points in the IMAAVY 30 mg/kg IV treatment group compared to placebo.5 Results are considered descriptive based on the study’s pre-specified statistical analysis plan6
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Karen Jones has not been compensated for any media work
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Dr. Kuter has served as a consultant to J&J; he has not been paid for any media work
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30 mg/kg q4w is the approved dose
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Durable Hgb response, as defined in Editor’s note “a,” was achieved with statistical significance in the approved 30 mg/kg IV q4w treatment group5
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Nurse Navigators do not provide medical advice
ABOUT THE ENERGY TRIAL
ENERGY (NCT04119050) is a multicenter, randomized, double-blind, placebo-controlled Phase 2/3 study evaluating the efficacy and safety of nipocalimab compared with placebo, followed by an open-label extension period, in adults living with warm autoimmune hemolytic anemia (wAIHA).7 115 adults were randomized approximately 1:1:1 to receive nipocalimab at two different dose schedules or placebo.7 Following completion of 24 weeks of double-blind treatment, patients could enter an open-label extension period to receive nipocalimab for 144 weeks with a follow-up period of 6 weeks after last assessment.7
ABOUT WARM AUTOIMMUNE HEMOLYTIC ANEMIA (wAIHA)
Warm autoimmune hemolytic anemia (wAIHA) is a rare, life-threatening condition where autoantibodies attach to and destroy red blood cells (RBCs), resulting in anemia.[8] Approximately 1-3 new people per 100,000 are affected by wAIHA per year, and about 1 in 8,000 individuals are living with the condition.8,9 This condition affects both women and men, and can affect people at any age with incidence increasing over the age of 50.9,10 Additionally, people with wAIHA are at increased risk of other serious complications such as venous thrombotic events, acute renal failure, and infection.11
ABOUT IMAAVY (nipocalimab-aahu)
IMAAVY® is an immunoselective treatment designed to target, bind with high affinity, and block the neonatal Fc receptor (FcRn), reducing circulating immunoglobulin G (IgG) antibodies that drive disease while also preserving B-cell function based on in vitro and/or in vivo studies.12,13 IMAAVY is currently approved for the treatment of generalized myasthenia gravis (gMG) in adults and pediatric patients 12 years of age and older who are anti-acetylcholine receptor (AChR) or anti-muscle-specific tyrosine kinase (MuSK) antibody positive.5 IMAAVY is also approved for the treatment of warm autoimmune hemolytic anemia (wAIHA) in adult and pediatric patients 12 years of age and older currently or previously treated with corticosteroids.5
Nipocalimab is being investigated across three key segments in the autoantibody space including Rheumatologic diseases, Rare Autoantibody diseases, and Maternal Fetal diseases mediated by maternal alloantibodies, in which blockade of IgG binding to FcRn in the placenta is believed to limit transplacental transfer of maternal alloantibodies to the fetus.14,15,16,17,18,19,20,21
The U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) have granted several key designations to nipocalimab including:
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EU EMA Orphan medicinal product designation for hemolytic disease of the fetus and newborn (HDFN) in October 2019 and fetal and neonatal alloimmune thrombocytopenia (FNAIT) in April 2025
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U.S. FDA Fast Track designation in HDFN, and warm autoimmune hemolytic anemia (wAIHA) in July 2019, gMG in December 2021, FNAIT in March 2024, Sjögren’s disease (SjD) in March 2025, and systemic lupus erythematosus (SLE) in January 2026
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U.S. FDA Orphan drug status for wAIHA in December 2019, HDFN in June 2020, gMG in February 2021, chronic inflammatory demyelinating polyneuropathy (CIDP) in October 2021 and FNAIT in December 2023
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U.S. FDA Breakthrough Therapy designation for HDFN in February 2024 and for SjD in November 2024
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U.S. FDA granted Priority Review in gMG in Q4 2024 and wAIHA in Q2 2026
The legal manufacturer for IMAAVY is Janssen Biotech, Inc.
ABOUT JOHNSON & JOHNSON
At Johnson & Johnson, we believe health is everything. Our strength in healthcare innovation empowers us to build a world where complex diseases are prevented, treated, and cured, where treatments are smarter and less invasive, and solutions are personal. Through our expertise in Innovative Medicine and MedTech, we are uniquely positioned to innovate across the full spectrum of healthcare solutions today to deliver the breakthroughs of tomorrow and profoundly impact health for humanity.
REFERENCES
1 Johnson & Johnson. Press Release: FDA grants Priority Review for IMAAVY® (nipocalimab-aahu) as the potential first approved treatment for people living with warm autoimmune hemolytic anemia (wAIHA). Available at: https://www.jnj.com/media-center/press-releases/fda-grants-priority-review-for-imaavy-nipocalimab-aahu-as-the-potential-first-approved-treatment-for-people-living-with-warm-autoimmune-hemolytic-anemia-waiha. Last accessed: April 2026.
2 Rarediseases.org. Warm Autoimmune Hemolytic Anemia. Available at https://rarediseases.org/rare-diseases/warm-autoimmune-hemolytic-anemia/. Last accessed: February 2025.
3 Sudulagunta SR, et al. Warm Autoimmune Hemolytic Anemia: Clinical Profile and Management. J Hematol. 2017 Mar; 6(1): 12–20. Published online 2017 Mar 21. doi: 10.14740/jh303w.
4 Fattizzo B, Murakhovskaya I, Ueda.Y, Schlichting D, Sweet K, Zelasky M, Craig J, Liva S, Leu J, Ling L, Pease S, Anakor A, Shu C, Nipocalimab for warm autoimmune hemolytic anemia: results from the Phase 2/3 randomized, double-blind ENERGY study, Presented at EHA 2026 Congress, Available at: https://library.ehaweb.org/eha/2026/eha-2026/4206854/bruno.fattizzo.nipocalimab.for.warm.autoimmune.hemolytic.anemia.results.from.html
5 IMAAVY® U.S. Prescribing Information.
6 J&J. Data on File.
7 ClinicalTrials.gov Identifier: NCT04119050. Available at: https://www.clinicaltrials.gov/study/NCT04119050
8 National Organization for Rare Disorders, Warm autoimmune Hemolytic Anemia. Available at: https://rarediseases.org/rare-diseases/warm-autoimmune-hemolytic-anemia/. Last accessed: February 2025.
9 Tranekær S, Hansen DL, Frederiksen H. Epidemiology of Secondary Warm Autoimmune Haemolytic Anaemia-A Systematic Review and Meta-Analysis. J Clin Med. 2021 Mar 17;10(6):1244. doi: 10.3390/jcm10061244. PMID: 33802848; PMCID: PMC8002719.
10 Cherif, H., Cai, Q., Crivera, C., Leon, A., Rahman, I., Leval, A., Noel, W. and Kjellander, C. (2024), Overall Survival and Treatment Patterns Among Patients With Warm Autoimmune Hemolytic Anemia in Sweden: A Nationwide Population-based Study. Eur J Haematol. https://doi.org/10.1111/ejh.14311.
11 Fattizzo B, Barcellini W. New Therapies for the Treatment of Warm Autoimmune Hemolytic Anemia. Transfusion Medical Reviews, Vol. 36, Issue 4. October 2022 https://doi.org/10.1016/j.tmrv.2022.08.001.
12 Ling LE., et al. M281, an anti‐fcrn antibody: Pharmacodynamics, pharmacokinetics, and safety across the full range of IGG reduction in a first‐in‐human study. Clinical Pharmacology & Therapeutics., 2018;105;4:1031–1039. Available at: https://doi.org/10.1002/cpt.1276.
13 Cossu M et al. A randomized, open-label study on the effect of nipocalimab vaccine response in healthy participants. Presentation at American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) Annual Meeting. October 2024.
14 ClinicalTrials.gov Identifier: NCT04951622. Available at: https://clinicaltrials.gov/ct2/show/NCT04951622. Last accessed: August 2026.
15ClinicalTrials.gov Identifier: NCT05327114. Available at: https://www.clinicaltrials.gov/study/NCT05327114. Last accessed: August 2026.
16 ClinicalTrials.gov Identifier: NCT04119050. Available at: https://clinicaltrials.gov/study/NCT04119050. Last accessed: August 2026.
17 ClinicalTrials.gov Identifier: NCT05379634. Available at: https://clinicaltrials.gov/study/NCT05379634. Last accessed: August 2026.
18 ClinicalTrials.gov Identifier: NCT05912517. Available at: https://www.clinicaltrials.gov/study/NCT05912517. Last accessed: August 2026.
19 ClinicalTrials.gov Identifier: NCT06533098 Available at: https://clinicaltrials.gov/study/NCT06533098. Last accessed: August 2026.
20 ClinicalTrials.gov Identifier: NCT06741969 Available at: https://clinicaltrials.gov/study/NCT06741969 Last accessed: August 2026.
21 ClinicalTrials.gov Identifier: NCT07438496 Available at: https://clinicaltrials.gov/study/NCT07438496 Last accessed: August 2026.